Planck isocurvature constraint on primordial black holes lighter than a kiloton

TaeHun Kim, Jinn-Ouk Gong, Donghui Jeong +3

We demonstrate that primordial black holes (PBHs) lighter than $10^9\text{g}$, which evaporated before the big bang nucleosynthesis, can induce significant isocurvature perturb…